To enhance drilling productivity, it is important to maximize the efficiency with which pipe sections can be loaded into and unloaded from a magazine. Until fairly recently, pipe sections were manually carried between the magazine and the pipe rotation mechanism of a drilling machine, and were also manually loaded into and unloaded from the magazine. Recent developments, however, have improved pipe loading and unloading efficiencies, primarily through automation. Still, misalignment between pipe sections and pipe rotation mechanisms resulting from settling or damaged drilling assemblies and pipe handlers requires adjustment of the alignment between pipe sections and pipe rotation mechanisms.
It is known to provide various assemblies and mechanisms for moving a pipe section between a magazine and a pipe rotation mechanism. More particularly, it is known to handle drill pipe using a device that is generally similar to a human forearm, elbow, wrist, and hand. With the arm down in the horizontal position, the gripper is rolled to receive a pipe from the side. The grippers grasp the pipe and roll 90 degrees about a horizontal axis to hold the pipe upward, yet still horizontal. Then the arm swings upward about a perpendicular horizontal axis to elevate the pipe to the vertical position and in alignment with the rotary spindle of the drilling rig. In these conventional assemblies, the alignment of the drill pipe to the pipe rotation mechanism almost always requires manual human contact with the pipe in order to push the pipe into final alignment so as to prevent cross-threading. This exposes humans to a dangerous environment where risk of injury is statistically very high. It also increases labor costs and reduces productivity of the drilling operation.
It is also known to use slotted parts, shims or rewelded parts for adjusting the alignment between a drill pipe and the spindle or quill of a pipe rotation mechanism on a drilling assembly. The conventional pipe handlers also suffer from one or more disadvantages. For example, the use of slotted parts, shims or rewelded parts requires very heavy and awkward components to be held precisely during retightening or reassembly. Further, the adjustments can only be made when the pipe handler arm is down. As a result, alignment cannot be checked after the adjustment is made until the handler arm is raised again. The adjustment of the alignment of conventional pipe handlers using slotted parts, shims or rewelded parts is also time consuming. Moreover, conventional pipe handlers using slotted parts, shims or rewelded parts to make adjustments to the alignment between the drill pipe and the pipe rotation mechanism cannot accommodate all possible combinations of misalignment so precise alignment is not possible in certain circumstances.
It would be desirable, therefore, if an apparatus and method for a pipe handler could be provided that would reduce the risk of injury to humans in connection with adjusting the alignment of a drill pipe to a pipe rotation mechanism. It would also be desirable if such an apparatus and method for a pipe handler could be provided that would reduce the amount of time and labor required to adjust the alignment between a drill pipe and the pipe rotation mechanism and increase the productivity of drilling operations. It would be further desirable if such an apparatus and method for a pipe handler could be provided that would permit adjustment of the alignment of a drill pipe to the pipe rotation mechanism while the pipe is held in alignment with the pipe rotation mechanism. It would be still further desirable if such an apparatus and method for a pipe handler could be provided that would permit the precise and infinite adjustment of the alignment between a drill pipe and the pipe rotation mechanism. It would also be desirable if such an apparatus and method for a pipe handler could be provided that would permit the adjustment of the alignment between a drill pipe and the pipe rotation mechanism when the drilling assembly or pipe handler settle or is damaged.